code: def file_name(self):
      return self._fname
  
file_path: ffcv/ffcv/reader.py
imports: import numpy
  from .utils import decode_null_terminated_string
  from .types import ALLOC_TABLE_TYPE, HeaderType, CURRENT_VERSION, FieldDescType, get_handlers, get_metadata_type
label_desc: Use image node_id 2 for calling the Reader obj's underlying member method code with example usage: obj.file_name() and returns: self